The proposed research is a program for an in-depth neurophysiological study of the dorsal spinocerebellar tract (DSCT) in the cat. There are now sufficient data regarding the incorporation of sensory information by DSCT neurons to question the widely accepted view of its function with respect to the cerebellum. Therefore, the specific aims of this proposal include a critical re-examination of response behavior of single DSCT units and populations of DSCT units to various forms of natural stimulation. The long-term objectives are to describe how sensory information is organized by a first-order spinal sensory nucleus that is specifically concerned with motor control and to use this information to supplement existing knowledge about cerebellar function.